\begin{table}%t1
\caption{Detection conditions for water ice bands. Upper layer: ICH$_4$ at 16~K. Lower layer: crystalline H$_2$O at 40~K.}\label{T1}
\small%\centerline
 {
\begin{tabular}{c c c c c c}
\hline \hline
$f$ & up-$t$ & up-$d_{\rm e}$ & lo-$d_{\rm e}$ & 3\% det. & 10\% det.\\
\hline
80\% & 5 $\mu$m & 5 $\mu$m & 20$-$200 $\mu$m & yes & yes\\
100\% & ?* & ?* & 20$-$200 $\mu$m & yes & yes\\
100\% & 5 $\mu$m & 5 $\mu$m & 20$-$200 $\mu$m & yes & no\\
100\% & 10 $\mu$m & 10 $\mu$m & 20$-$200 $\mu$m & no & no\\
\hline
\end{tabular}}
\medskip
*$d_{\rm e}<$ 5 $\mu$m would violate the Hapke theory in this range.
\end{table}